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Catalyst 6500 Series Switch and Cisco 7600 Series Router Firewall Services Module Configuration Guide using ASDM
OL-20748-01
Chapter 14 Configuring Failover
Understanding Failover
Failover System Requirements
This section describes the software and license requirements for FWSMs in a failover configuration.
This section includes the following topics:
•
Software Requirements, page 14-2
•
License Requirements, page 14-2
Software Requirements
The two units in a failover configuration must have the same major (first number) and minor (second
number) software version. However, you can use different versions of the software during an upgrade
process; for example, you can upgrade one unit from Version 3.1(1) to Version 3.1(2) and have failover
remain active. We recommend upgrading both units to the same version to ensure long-term
compatibility.
License Requirements
Both units must have the same license. In the occurrence of a license mismatch, a failover pair enters
pseudo-standby mode, a condition in which failover is disabled. FWSMs in an active/active
configuration return to the active/standby state and do not pass any traffic.
Failover and State Links
This section describes the failover and the state links, which are dedicated connections between the two
units in a failover configuration. This section includes the following topics:
•
Failover Link, page 14-2
•
State Link, page 14-3
Failover Link
The two units in a failover pair constantly communicate over a failover link to determine the operating
status of each unit. The following information is communicated over the failover link:
•
The unit state (active or standby).
•
Hello messages (keep-alives).
•
Network link status.
•
MAC address exchange.
•
Configuration replication and synchronization.
Caution
All information sent over the failover and Stateful Failover links is sent in clear text unless you secure
the communication with a failover key.
Summary of Contents for 6500 - Catalyst Series 10 Gigabit EN Interface Module Expansion
Page 35: ...P A R T 1 Getting Started and General Information ...
Page 36: ......
Page 297: ...P A R T 2 Configuring the Security Policy ...
Page 298: ......
Page 521: ...P A R T 3 System Administration ...
Page 522: ......
Page 613: ...P A R T 4 Reference ...
Page 614: ......